Kızıleniş, Çağlayan
9H-xanthene (10H-9-oxaanthracene or Xanthene) core based Photodynamic Therapy (PDT) agents became highly sought after since they demonstrated numerous advantages including a high molar extinction coefficient, high photostability, high light-dark toxicity ratio, and availability for both lipophilic and aqueous media. The tunability of the xanthene core makes it a great candidate for imaging and therapeutic purposes. For PDT action, the agent should have a high singlet oxygen generation yield, absorb at the therapeutic window, localize at the subcells, and have a desired hydrophilicity among other factors. In this study, novel low molecular weight, red absorbing, and water-soluble silicon (SiNO-OMe, SiNO-OMe2) and phosphine oxide (PNN, Morp) containing xanthene dyes were designed and significant effort has been dedicated to their synthesis. Synthesis of one of the desired silicon containing xanthene dyes was confirmed in High Resolution Mass Spectrometry (HRMS), however isolation of the target has not been fruitful so far. For the synthesis of silicon containing derivatives, several trials were performed for a key demethylation reaction and a nitrosonium based approach for forming a nitrogen bridge on the xanthene core as a new concise synthetic approach was detailly pursued. Aminopeptidase N targeting handle (APN) was synthesized for modifying novel cores pursued in this study to achieve selective accumulation on brain cancer (glioblastoma cells). In the second chapter, a Two Photon Absorption dye, TPA, was designed, and the donor and acceptor components of this dye (compounds 3.5 and 3.7) were successfully synthesized. As a future work synthesis of SiNO-OMe, PNN-Morp, and TPA will be finalized and their photophysical properties will be investigated. Their aminopeptidase N caged derivatives will also be realized and their performance in in vitro studies will be investigated.
Citation Formats
Ç. Kızıleniş, “TOWARDS LOW MOLECULAR WEIGHT XANTHENE-BASED DYES WITH ABSORPTION BEYOND 650 NM,” M.S. - Master of Science, Middle East Technical University, 2024.